Eyepiece for gas masks



Nov. 17, 1936. OLEARY 2,060,823

EYEPIECE FOR GAS MASKS Filed Aug. 24, 1955 INVENTOR THQMRJ 9. O'L EmQ vATTORNEY Patented Nov. 17, 1936 UNITED STATES PATENT OFFICE 4 Claims.

The invention relatesto the eyepiece portion of a gas mask. One objectof the invention is to provide improved means for securing the lens tothe tubular members which project forwardly 5 from the body of the mask,and moreparticularly when such parts are of soft molded rubber. Afurther object is to provide a union for carrying the lens, which shallbe permanent and which will not reduce the life of the rubber.

l0 Heretofore the means for mounting the lens in masks has tended tostretch and distort therubber or fabric adjacent thereto to such anextent as to cause an accelerated deadening or deterioration ofthematerial resulting often in a failure of the seal at this point andleakage impairing the safety of the mask. The present invention is dsigned to overcome this defect-and provide union or mounting forthelens, which shall be securely sealed, but without imposing upon therubber any strain which will iimpair its life; which holds the lens verysecurely against accidental displacement; and

a which permits of ready replacement of the lens "in case of breakage.One embodiment of the invention is shown in the accompanying drawing,wherein:

Figure 1 is a section through the tubular member which constitutes thesupport for the lens. Fig. 21s a similar view showing the parts,including the lens and securing parts, in assembled relation preliminaryto clamping them together. And- Fig. '3 is a section showing thecompleted assembly in clamped relation.

Referring to the drawing, I is one of the tubuof the mask being of softrubber of the full molded type permitting the employment of thin andthicker portions at will, the material, as shown, being preformed sothat it retains its shape. The first step in the assembly is theapplication of the base ring 2, which is easily positioned by collapsingthe end of the rubber tube. This ring may be of any material, but ispreferably steel carrying a rust proof coating. The lens of glass, orother transparent material; is then seated on the top of the tube, anda' sealing ring 3 of soft'rubber, or the like, is laid on the glass,followed by the application of the retaining ring 4, as indicated inFig. 2. This ring may be of any suitable material, preferably brass withgood drawing qualities.

The final step isthe crimping over of the lower edge of the ring 4, asindicated in Fig. 3. In such operation the bead 5 and the sealing ring 3are compressed slightly, so as to insure a seal, such compression notbeing sufficient, however, to impair the life of the rubber. The bead 5is preferably wedge-shaped, as shown, so that when the parts are inclamped position, as shown in n Fig. 3, the bead is securely grippedbetween the lar members for carrying the lens, this portion edge of thelens and the ring 2 and. it is practically impossible to accidentallycollapse the wall of the tube so as to release. the head from theretaining ring. This detail of construction renders the mounting of thelens permanent and safe against'leakage under severe conditions ofhandling and use.

What I claim is:

1. In a gas mask construction, a tubular support of yielding moldedmaterial having a laterally projecting bead around its outer end ofwedge shape with the portion of least thickness at its inner edge, alens seated on the end of the tube,- a base ring around the tube fittingagainst the side .of the bead remote from the lens, and a retaining ringwhich is angular in cross section having one flange lying over themargin of the lens and the other flange extending across the edge of thebead and having its extreme edge turned inwardly around the edge of thebase ring so as to lock it in position.

2. In a gas mask'construction, a tubular support of soft molded rubberhaving a laterally projecting bead around its outer end of wedge shapewith the portion of least thickness at its inner edge, a lens seated onthe end of the tube, 'a .base ring around the tube fitting against theside of the bead remote from the lens, and a retaining ring which isangular in cross section having one flange lying over the margin of thelens and the other flange extending across the edge of the bead andhaving its extreme edge turned inwardly around the edge of the base ringso as to lock it in position.

3. In a gas mask construction, a tubular support of yielding moldedmaterial having a laterally projecting bead around its outer end ofwedge shape with the portion of least thickness at its inner edge, alens seated on the end of the tube, a base ring around the tube fittingagainst the sideof the bead remote from the lens, a sealing ring ofyielding material on the margin of the lens, and a retaining ring whichis angular in cross section having one flange lying over said sealingring and the other flange extending across the edge of the bead andhaving its extreme edge turned inwardly around the edge of the base ringso as to lock it in position.

4. In a gas mask construction, a tubular support of yielding moldedmaterial having a laterally projecting bead around its outer end ofwedge shape with the portion of least thickness at its inner edge, apair of clamping rings on opposite sides of the head, a lens on the endof the tube between the rings, a ring of yielding sealing materialbetween the lens and one of the rings, and means for clamping the ringstogether so as to maintain the bead under compression.

THOMAS A. OLEARY.

